|1||Atoll (an oceanic low island of coral origin, e.g. Ulithi)||20|
|2||Volcanic high island (an oceanic island of volcanic origin, e.g. Hawaii)||61|
|3||Tectonic (an oceanic island formed by tectonic uplift, e.g. Macquarie Island)||14|
|4||Continental island (an island situated on a continental shelf, e.g. Taiwan)||37|
Islands that are connected by tidal zones should be considered one island. However, when measuring island size, only areas of land that are permanently above sea level should be included.